By the time the Falklands War broke out in 1982, Leake was serving as a Canteen Manager in the Naval Canteen Service wing of the NAAFI on board HMS Ardent, a Royal NavyType 21 frigate. His role on board the ship was to run an onboard shop selling confectionery, cigarettes, beer and toiletries to other members of the crew. The ship was ordered to proceed to Ascension Island, where after three days it proceeded to the Falklands. On the morning of7 May, he was invited to practice on a general-purpose machine gun, being informed afterwards that he was to take up that role instead at action stations should active service be declared, with his former role of casualty coordinator in sickbay being taken by his Canteen Assistant, Nigel Woods. While en route, active service was declared and Leake signed on to the Royal Navy on a temporary basis, becoming a petty officer in the Royal Navy, but continuing in his previous role as Canteen Manager. Being a member of the Navy allowed him to be covered by the protections of the Geneva Convention. On 21 May, the Ardent moved into position in Falkland Sound as the lead ship to bombard Argentine positions in order to divert the attention of the enemy force from the British landing in the San Carlo inlet. Leake operated a deck mounted machine gun during the ensuing attacks by Argentine aircraft, and was credited with downing an Argentine Douglas A-4 Skyhawk, puncturing the plane's fuel tanks. He continued to man the gun whilst the ship was hit by seventeen missiles and bombs. Along with the remaining crew, Leake abandoned ship, boarding HMS Yarmouth, which pulled alongside the listing Ardent. Leake was later posted to HMS Sutherland, and died on 13 February 2000 in St Luke's Hospice, Plymouth, from cancer after previously having a kidney removed in an attempt to beat the disease. His funeral took place at the crematorium at Weston Mill, Plymouth on 21 February 2000.
Private life
He married Carole, and together they had a son as well as two sons from Carole's previous marriage. At the time of his death, he was living in Milehouse, Plymouth. He was one of five brothers, the others being David, Ian, Geoffrey, and Stephen
Legacy
, the commander of the British Naval Force during the Falklands War, wrote about Leake in his memoirs. He said "I was sure there would be many stories of heroism to come out of it, but of them all, I remain most impressed by the conduct of John Leake who manned the machine gun in Ardent. He was not really in the Navy, but, as we say, we are all of one company, the Captain and the NAAFI man. And we all go together." Following Leake's death in 2000, his medals were put up for auction on 23 September 2011. The initial estimate expected the medals to be sold for up to £50,000. It instead sold for £110,000, beating the previous record paid for a Distinguished Service Medal set at £59,800 in 2003.